private static IFuzzyNumber Operation(Func<double, double, double> f, IFuzzyNumber y, IFuzzyNumber x)
{
var resultLevels = new Dictionary<double, IntervalD>();
y.ForeachLevel((alpha, leftLevel) =>
{
var rightLevel = x.GetAlphaLevel(alpha);
var leftProduct = f(leftLevel.X, rightLevel.X);
var leftRightProduct = f(leftLevel.X, rightLevel.Y);
var rightLeftProduct = f(leftLevel.Y, rightLevel.X);
var rightProduct = f(leftLevel.Y, rightLevel.Y);
var left = Math.Min(Math.Min(leftProduct, leftRightProduct),
Math.Min(rightProduct, rightLeftProduct));
var right = Math.Max(Math.Max(leftProduct, leftRightProduct),
Math.Max(rightProduct, rightLeftProduct));
resultLevels.Add(alpha, new IntervalD(left, right));
});
return new DiscreteFuzzyNumber(resultLevels);
}
public IFuzzyNumber Sum(IFuzzyNumber x)
{
var resultLevels = new Dictionary<double, IntervalD>();
foreach (var leftlevel in _alphaLevels)
{
var rightLevel = x.GetAlphaLevel(leftlevel.Key);
resultLevels.Add(leftlevel.Key, rightLevel + leftlevel.Value);
}
return new DiscreteFuzzyNumber(resultLevels);
}